class Student {

    constructor(name) {
        this.name = name;
    }

    sayHi(){
        console.log("Hi !" + this.name)
    }
}

class ArtStudent extends Student{
    constructor(age) {
        super();
        this.age = age;
    }
}
let name = 123;
let jxc = new Student(name);
let jxc2 = new ArtStudent(321);


